Z. Kołakowski and M. Królak, “Interactive Elastic Buckling of Thin-Walled Closed Orthotropic Beam-Columns”, Eng. Trans., vol. 43, no. 4, pp. 571–590, Dec. 1995, Accessed: Jul. 13, 2025. [Online]. Available: https://et.ippt.pan.pl/index.php/et/article/view/1518